Yemen's Houthi rebels held a funeral on Monday for their prime minister and 11 other senior officials killed in an Israeli air strike that decimated its political cabinet.

Twelve coffins draped in flags were displayed at Sanaa's Al-Shaab mosque, as masked gunmen patrolled the area and thousands of mourners flooded in.

Huthi prime minister Ahmed Ghaleb Nasser al-Rahawi, nine ministers and two cabinet officials were killed as they attended a government meeting in the Sanaa area on Thursday.

It was the highest profile assassination to be announced in Yemen in months of attacks by Israel during the Gaza war. The United States also waged an intense bombing campaign against Huthi targets from March to May this year.

The missile landed close to the Liberian-flagged Scarlet Ray with a "loud bang", the UK Maritime Trade Operations monitoring agency said.

- 'Bad day' for Houthis -

The Huthis, part of Iran's "axis of resistance" of anti-Israeli groups, vowed to step up their attacks on Israel following Thursday's killings.

Their campaign of missile and drone strikes at Israel and on shipping in the Red Sea, a major cargo route, has persisted throughout the Gaza war, claiming solidarity with the Palestinians.

Last week's Israeli strike wiped out about half of the 22-strong Huthi cabinet, which plays a mainly administrative role.

Rahawi, the late prime minister, was from the southern province of Abyan, which is not part of the large swathes of Yemen under Huthi control.

The Houthis, who hail from divided Yemen's rugged north, have traditionally reserved the premiership for southerners in an attempt to win hearts and minds.

US-based Yemen analyst Mohammed Al Basha said Thursday's strike may signal an Israeli shift towards targeted killings, an approach that gutted the leadership of Gaza rulers Hamas and Hezbollah in Lebanon.

The attack could mark "the beginning of a campaign of targeted assassinations against both civilian and military Huthi leadership, even at informal gatherings", he posted on X, calling it a "bad day" for the group.